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08-71520-00
3. CAUTIONS
If 100% of anti-freeze is added, the water pump vane can be damaged and thermal conductivity
can be decreased resulting in poor circulation in the cooling system which leads to overheated
engine.
Use of non-recommended coolant could cause damage to the cooling system and overheating of
the engine.
Opening the coolant reservoir cap while the engine is running or hot can cause burns by hot steam
or water.
To open the coolant reservoir cap, wrap the cap with a wet towel or thick cloth after the engine is
cooled down sufficiently.
If cool water is added to the heated engine, the engine or radiator can be deformed.
The anti-freeze in the coolant can damage the painted surface, so avoid the contact of the coolant
to the painted body.
The anti-freeze and water should be mixed in proper mixture ratio. Never add only water when
adding coolant.
If the anti-freeze content is too low, the coolant can be frozen while the engine can be overheated if
anti-freeze content is too high. -
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08-8
Oil filter module
Thermostat
When the engine coolant
reaches 90℃, the thermostat
starts to open (fully open at
100℃) and lets the coolant
flow to the radiator to maintain
the engine temperature.
Water pump
The water pump is driven by the engine drive belt and supplies
the coolant to each area of the engine.
Coolant reservoir
Long life coolant is used.
1. SYSTEM DESCRIPTION
1) Overview
Water pump
Impeller vane Sealing
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08-91520-00
Electric fan
Circulates the fresh air forcibly to exchange heat
with the radiator core fin.
Radiator
Releases heat through fins and cools down the hot
coolant as the coolant passes through the tube of the
radiator core.
Coolant temperature sensor
Measures the coolant
temperature and sends the
result to the engine ECU.
Page 148 of 751
09-31451-01
1. SPECIFICATION
AlternatorCrankshaft pulley : Alternator pulley 1 : 2.94
Normal output (idling/2200 rpm) 70/120 A
Regulator voltage 14.6 V
BrushLength 12.5 mm
Wear limit 7 mm
BatteryType MF
Capacity 90 AH
Unit Description Specification
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09-4
2. INSPECTION
1) Alternator Output Test
Item How to check DTC set value / Action
Output
current
B terminal
current
Rotor
coil
resistance
L terminal
voltage
Disconnect the cable connected to the B
terminal on the alternator. Connect one end
of the ammeter to the B terminal and the
other end to the cable connected to the B
terminal.
Measure the maximum output value.
(Maintain the engine speed between 2,500
and 3,000 rpm.)
(Turn the headlamp and all the electrical
switches on.) 1.
2.Pass: If the measured current is 45
A or higher.
Fail: If the measured current is less
than 45 A.
Check the current of the B terminal. -
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Move the gear selector lever to the neutral
position.
Maintain the engine speed at 2,500 rpm
with the vehicle unloaded.
(Turn all the electrical switches off.) 1.
2.Open circuit: If the measured
current is 5 A or higher. -
Disconnect the negative cable from the
battery.
Remove the B terminal and turn off the
ignition switch.
Measure the resistance between the L and
F terminals with an ohmmeter. 1.
2.
3.Pass: If the measured resistance is
between 3 and 6 Ω.
Faulty rotor coil or slip ring: If the
measured resistance is less than
3 Ω or greater than 6 Ω. -
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Connect the B terminal wiring.
Measure the voltage with the engine running. 1.
2.Specification: 12.5 V to 14.5 V
Faulty IC regulator or field coil: If
the measured voltage is 14.5 V or
higher. -
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Disconnect the negative battery cable.
Connect the negative cable again after connecting the ammeter. -
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09-51451-01
2) Troubleshooting for Alternator
Item Cause Action
Overcharged batteryDefective alternator voltage regulator
Replace the alternator
Defective voltage detection wiring Repair or replace
Loose alternator drive belt Adjust the belt tension or replace
Discharged batteryPoor connection of related circuit or open
circuitRetighten the loose connection or
repair open circuit
Defective alternator voltage regulator
Replace the alternator
Defective alternator voltage regulator
Replace the alternator
Terminated battery Replace the battery
Defective ground Repair
Charge warning
lamp does not come
on when turning on
ignition switch with
engine stoppedDefective alternator voltage regulator
Replace the alternator
Open circuit in charge warning lamp, fuse
or wiringReplace or repair the charge warning
lamp or fuse
Defective ignition switch Replace the ignition switch
Defective ground of alternator circuit Repair
Charge warning
lamp is not turned
off after starting
engineDefective alternator voltage regulator
Replace the alternator
Corroded or worn battery cableRepair or replace the battery cable
Loose alternator drive belReplace the batteryAdjust the belt
tension or replace the belt
Defective wiring harness Repair or replace
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09-71451-01
(1) Checking
Using battery tester ▶
PASS (11.0 V or more): Explain to the customer that the battery is reusable.
Need to be charged (9.0 to 11.0 V): Charge the battery with a charger and reinstall it. Explain it to the
customer.
Need to be replaced (9.0 V or more): The battery should be replaced due to overdischarging. -
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(2) How to use battery tester
How it works and How to use it ▶
Determine battery capacity by fixing current
(load capacity) and time and varying voltage.
Determine battery capacity based on the
amount of voltage drop when discharging a
fixed load capacity (120 A) for 5 seconds.
Connect the tester to the battery and read the
display while applying a load for 5 seconds. -
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How to read display ▶
Red area (①): overdischarge or faulty
battery
Yellow area (②): Need to be charged (using
a vehicle alternator and a battery charger)
Green area (③): Normal
Red area on the left-hand side of OK (④):
Impossible to charge with an alternator
Green area with OK (⑤): Normally charged
Red area on the right-hand side of OK (⑥):
Overcharged by an alternator태 -
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